The invention relates to a hoisting rope arrangement in a crane trolley, wherein the trolley is arranged to move on a main girder of the crane; a lifting mechanism of the trolley is located outside the trolley; both sides of the trolley are provided with successive rope pulley pairs located at a distance from one another in a longitudinal direction of the trolley and, below these, at a distance, sheaves situated in a hoisting member; whereby on both sides of the trolley, a first hoisting rope is led from a first end of the main girder of the crane via one rope pulley of a first rope pulley pair of the trolley down to the sheave located therebelow and therefrom via an other rope pulley of said rope pulley pair to a second end of the main girder; and on both sides of the trolley, a second hoisting rope is led from the second end of the main girder of the crane via one rope pulley of the second rope pulley pair of the trolley down to the sheave therebelow and therefrom via an other rope pulley of said rope pulley pair to the first end of the main girder.
Successive suspensions for hoisting ropes in the trolley should be made symmetrical so as to make a load to be distributed among the hoisting ropes as evenly as possible. When using a trolley wherein the lifting mechanism is located outside the trolley, the ropes are led to the hoisting member by running them via rope pulleys provided in the trolley. Typically, building a symmetrical rope suspension requires successive rope pulley pairs to be placed at different distances from the trolley so as to prevent the rope lines from coming into contact with one another. One such prior art solution is disclosed in document JP 1990243494A wherein hoisting ropes led to opposite sides of the crane then both run in parallel planes of their own, thus requiring space in the width direction. As viewed from above, the trolley and its rope pulley fastenings are not symmetrical, either.